GovernDiff

Policy changes, reviewed like code.

GovernDiff is local-first Policy CI for PDF, DOCX, HTML, Markdown, and text. It aligns clauses even when they move, detects review-worthy changes to duties, scope, deadlines, exceptions, and authority, and produces evidence a person can verify. No document upload or LLM is required.

Live demo · PyPI · GitHub Action Marketplace · Release · Feedback / boundary cases · Technical article · 30-second walkthrough · Why GovernDiff? · Input boundaries · Public repository policy · GitHub Action

Before: Vendors may report incidents within 72 hours.
After:  Vendors must report incidents within 24 hours.

GovernDiff: modality-strengthened · deadline-shortened · CI gate failed

Try it now

Install the published package and generate a self-contained HTML report from two local policy files:

python -m pip install governdiff
governdiff diff old-policy.md new-policy.md --format html --output report.html

Try the synthetic demo · Use the GitHub Action

What you get

• Deterministic English and Chinese checks with stable GVD-* fingerprints
• Before/after evidence locations, confidence reasons, and four report formats
• A local Reviewer for human decisions, field corrections, and portable waivers
• A pull-request gate that retains complete evidence even when the check fails

Breaking is a deterministic review cue, not a legal-risk, policy-effect, or compliance conclusion. A responsible human reviewer must verify important changes and their source evidence.

中文简介：GovernDiff 把政策、章程、行为准则等自然语言文件当作“可审查代码”， 识别新增义务、限制、权限主体、范围、例外、期限和数值阈值的变化，并可在 CI 中阻断 未经审查的高风险变更。完整产品定义见 GOVERNDIFF_PRD.md。

What works in v0.6

The authoritative v0.6 release boundary and all FR/NFR dispositions are recorded in docs/REQUIREMENTS_TRACEABILITY_MATRIX.zh-CN.md. Longer-term PRD items are not implied release promises.

• Digital PDF parsing with physical pages, paragraph evidence, scan detection, and repeated header/footer suppression
• DOCX headings, paragraphs, real lists, tables, and paragraph indices
• HTML policy-body extraction with site-chrome, script, and style removal
• Markdown and text parsing with section, line, paragraph, and character evidence
• Actionable preflight for empty, corrupt, encrypted, garbled, low-coverage, and image-only inputs
• A shared table/cell model whose DOCX and HTML cells participate in comparison
• 25 MB and 300-page hard limits with reason, impact, and next-step diagnostics
• Clause alignment across edits, moves, one-to-many splits, and many-to-one merges
• Added, removed, modified, split, merged, moved, and format-only classification
• Token-level equal/insert/delete/replace spans for English and Chinese evidence
• Explainable English and Chinese breaking checks
• The 15-check v0.6 contract: modality strengthened/weakened, permission removed, prohibition added, scope expanded/narrowed, authority shifted, deadline shortened/extended, threshold changed, exception added/removed, effective date shifted, definition changed, and reference retargeted
• Stable GVD-* finding fingerprints and dated, approver-attributed waivers
• Explainable high / medium / low confidence on every change and finding
• Evidence-backed article-number remapping, including ranked candidates, competition scores, and unresolved conflict states
• Cross-reference retargeting and structured effective-date/deadline changes
• A report-level chapter tree with change, Breaking, type, and confidence counts
• JSON, Markdown, self-contained HTML, and one-finding-per-row CSV reports
• Shared all / breaking / confirmed / unreviewed / filtered export scopes
• Redacted exports that remove full block/table text and bound evidence excerpts
• Generator, timestamp, complete document hashes, scope metadata, and the non-legal-advice disclaimer in every format
• Published report 1.5, review 1.1, and waiver 1.0 JSON Schemas with checked-in examples and a compatibility policy
• diff, changelog, breaking, one-command local review, and Git-baseline check commands
• A release-ready composite GitHub Action with automatic PR-base globs, added/deleted files, compact Job Summary, complete artifacts, and confidence-aware gating
• Standard unreviewed / confirmed / rejected / modified / waived review states in report schema 1.5
• Machine/effective dual values for human-edited actor, deadline, scope, and other extracted fields
• Portable governdiff-review/1.1 export and CLI re-import, including alignment repair and reviewer notes
• A browser Reviewer UI with batch decisions, persistent quality warnings, waiver generation, project clearing, and keyboard/screen-reader support
• Three synthetic end-to-end fixtures covering deadlines, scope, exceptions, and authority

OCR, URL import, optional AI, result caching, public Reviewer hosting, and direct PR-page review interactions remain outside the current release. The CLI, Action, and local-first review workflow are usable with all five supported formats.

Supported environment and current verification

Surface	Declared support	Pre-release verification boundary
Python CLI	CPython 3.10–3.13	Windows local matrix; hosted Ubuntu and macOS remain release gates
Local Reviewer	Node.js 22.13 or newer	Node 22.13, latest 22 LTS, and latest 24 LTS on Windows
Inputs	PDF, DOCX, HTML, Markdown, plain text	Digital text only; image-only PDF is diagnosed and OCR is not performed
Reports	JSON, Markdown, self-contained HTML, CSV	Browser printing/PDF is not a supported export contract
Browser review	Current Chrome/Chromium	Automated DOM, layout, keyboard, axe, and performance gates; visible Chrome and assistive-technology sign-off remain manual release gates

Policy text and reviewer decisions stay local. GovernDiff has no telemetry, account, remote document store, or public processing service in this release.

Quick start

Python 3.10+ is required. The interactive local Reviewer additionally requires Node.js 22.13+. Install the current release from PyPI:

python -m pip install governdiff
governdiff diff old-policy.md new-policy.md --format html --output report.html
governdiff review old-policy.md new-policy.md --output-dir reviewed

From a source checkout, install the current tree directly:

python -m pip install .

For contributors working from this source tree:

python -m pip install -e .
governdiff breaking \
  examples/public-cases/01-incident-deadline/old.md \
  examples/public-cases/01-incident-deadline/new.md

Without installing, run directly from a clone:

PYTHONPATH=src python -m governdiff diff old-policy.md new-policy.md

PowerShell equivalent:

$env:PYTHONPATH = "src"
python -m governdiff diff old-policy.md new-policy.md

Uninstall the package with:

python -m pip uninstall governdiff

If a command fails, first run governdiff preflight <document> --format json. Each input diagnostic includes a reason, impact, and next step. A local review that was closed before export must be started again; completed final reports are never stored on a remote service. If an output file is locked or its directory is read-only, choose a writable output path and rerun the command—the previous valid file is left intact.

Generate JSON for another tool:

governdiff diff old.md new.md --format json --output report.json

Generate a single-file HTML report that opens without a server, or a CSV with one finding per data row:

governdiff diff old.md new.md --format html --output report.html
governdiff diff old.md new.md --format csv --output findings.csv

Every format uses the same scope and filter model:

governdiff diff old.md new.md --scope confirmed --format html --output confirmed.html
governdiff diff old.md new.md --scope unreviewed --format csv --output queue.csv
governdiff diff old.md new.md --scope filtered \
  --filter-check deadline-shortened --filter-severity high --format json

To export exactly the changes visible in the Reviewer, export its review JSON, re-import it with --review, and select --scope filtered. The review file carries the visible change fingerprints. Add --redacted to any format to remove full block/table text and bound evidence/value excerpts.

Re-apply a Reviewer decision log so decisions and human field edits affect the CLI report:

governdiff diff old.md new.md --review governdiff-review.json --format json --output reviewed-report.json

Run the complete local review loop without manually moving report or review files:

governdiff review old.pdf new.pdf --output-dir reviewed

This preflights and compares both inputs, starts the Reviewer only on 127.0.0.1, opens the generated report, receives the exported review, reapplies it, and writes final JSON, Markdown, self-contained HTML, and CSV reports. Use --port, --language, --config, --review, --no-open, or --redacted as needed. The random session token is passed over child-process stdin and stored only in an HttpOnly, SameSite cookie; it never appears in the URL. Temporary artifacts are removed after confirmation, or can be retained explicitly with --keep-session.

Preflight a document before comparison:

governdiff preflight policy.pdf
governdiff preflight handbook.docx --format json

Image-only PDFs are identified, but GovernDiff does not run OCR. See docs/INPUT_FORMATS.md for evidence fields, limits, error codes, and the explicit OCR boundary.

Show only unwaived breaking findings:

governdiff breaking old.md new.md --min-confidence medium

Every score is accompanied by machine-readable reasons. high begins at 0.80, medium at 0.62; lower scores remain visible rather than being silently discarded. Article mappings are emitted at report level and attached to affected changes, for example Article 4 → Article 5 or 第二条 → 第三条.

Policy CI

Copy governdiff.example.yml to .governdiff.yml, adjust the document globs, then compare working-tree policies with a Git baseline:

governdiff check --base origin/main --config .governdiff.yml

Exit codes are 0 for pass, 1 for a tool/configuration error, and 2 when an active finding reaches both checks.fail_on and checks.min_confidence.

Waivers live in .governdiff-waivers.yml:

schema_version: governdiff-waiver/1.0
waivers:
  - fingerprint: GVD-0123456789
    reason: Approved by the governance council in decision 2026-08.
    approved_by: Governance Council
    created_at: 2026-08-09T08:14:00+00:00
    expires_at: 2027-08-09

reason, approved_by, created_at, and expires_at are required. Expired waivers are not applied and appear as explicit report diagnostics. The 0.6 loader still accepts legacy approver as a migration alias.

Public schemas

Versioned contracts and examples live under schema/:

• report.schema.json — report 1.5;
• review.schema.json — governdiff-review/1.1;
• waiver.schema.json — governdiff-waiver/1.0;
• action-manifest.schema.json — governdiff-action/1.0 aggregate Action runs;
• COMPATIBILITY.md — additive 1.x changes, deprecation, and 2.0 conditions.

Validate all checked-in examples plus a live engine report without installing a schema-validation dependency:

PYTHONPATH=src python scripts/validate_schemas.py

GitHub Action

Use the stable v1 channel as a composite Action. In a pull request it resolves the base SHA automatically, selects only changed files matching a single path or glob, and handles modified, added, deleted, and renamed policies. Each file gets full JSON, Markdown, self-contained HTML, and CSV reports.

steps:
  - uses: actions/checkout@v6
  - uses: haiqi825-arch/governdiff@v1
    with:
      paths: |
        GOVERNANCE.md
        SECURITY.md
        policies/**/*.md
        policies/**/*.pdf
        policies/**/*.docx
        policies/**/*.html
      min-confidence: medium
      fail-on-severity: high
      fail-on-breaking: "true"

The compact Job Summary reports gate reason, per-file counts, stable finding fingerprints, and the actual uploaded artifact URL. The artifact contains manifest.json, summary.md, and four complete formats under each file's report directory. Outputs include action-schema, release-channel, gate-failed, files-audited, breaking-count, report-manifest, report-summary, report-dir, and artifact-url. The legacy old/new inputs and single-file report outputs remain available for explicit version pairs. Set fail-on-breaking: "false" for an advisory rollout while retaining annotations and complete evidence.

See docs/ACTION_RELEASE_POLICY.md for immutable v1.x.y, compatible v1, and commit-SHA pinning rules.

The bundled artifact step uses actions/upload-artifact@v7 and therefore targets GitHub.com/GitHub Enterprise Cloud. GitHub Enterprise Server does not currently support upload-artifact@v4+; GHES consumers must replace or disable that step rather than assuming artifact parity.

Reviewer UI

The standalone app lives in reviewer-ui/ and opens any GovernDiff report.json. It supports chapter, change-type, confidence, Breaking, review-status, and text filters; displays word-level evidence and competing article mappings; edits extracted fields without overwriting machine values; performs batch decisions; keeps quality warnings visible; stores review and manual alignment decisions in an atomic IndexedDB project; generates waiver YAML; and imports or exports a portable governdiff-review/1.1 decision log. The CLI accepts that log with --review. When started through governdiff review, the workspace uses an isolated, loopback-backed temporary session rather than the normal IndexedDB project, and returns Export directly to the waiting CLI.

cd reviewer-ui
npm ci
npm run dev

No policy text or reviewer decision leaves the machine. The CLI session server has no CORS permission and rejects non-loopback Host, cross-origin requests, invalid session cookies, and unexpected methods.

Three synthetic end-to-end examples live under examples/public-cases/. Publication-safe screenshots and a short demo are under docs/assets/; external regression corpora are not included in Python release artifacts. See docs/CORPUS_LICENSE_AUDIT.md before publishing any repository snapshot or corpus file.

Tests

PYTHONPATH=src python -m unittest discover -s tests -v

The Phase 2 format fixtures and failure cases live in tests/format_fixtures/. Rebuild them with python scripts/build_format_fixtures.py.

The focused Phase 3 benchmark covers split, merge, word replacement, cross-reference, effective-date, mapping-conflict, and section-tree behavior:

python scripts/evaluate_phase3_benchmark.py --strict

The Phase 6 suite creates an isolated real Git repository with two commits and tests modified, added, deleted, renamed, and ignored files without mocking Git:

PYTHONPATH=src python -m unittest tests.test_phase6 -v

Phase 7 adds strict privacy, performance, platform, supply-chain, and clean-build gates. The local evidence can be reproduced with:

PYTHONPATH=src python -m unittest tests.test_phase7 -v
python scripts/verify_zero_egress.py
python scripts/benchmark_phase7.py --strict
python scripts/verify_reproducible_builds.py
cd reviewer-ui
npm run test:performance
npm run test:browser
npm run test:reproducible
npm audit --audit-level=high

The checked-in CI matrix installs the package and generates JSON/HTML reports on Windows, macOS, and Linux. It also runs Dependabot, CodeQL, Python/npm audits, and an Anchore scan over the assembled Python wheel and Reviewer build. See docs/PHASE_7_COMPLETION.zh-CN.md for the measured results and the current no-remote hosted-run boundary.

Phase 7.6 promotes the Reviewer gate to a real Chrome/React/DOM/layout test with a deterministic 5,000-change report, bounded list rendering, recovery and local session paths, responsive checks, keyboard/focus assertions, and axe-core. See docs/PHASE_7_6_COMPLETION.zh-CN.md and benchmark/PHASE_7_6_BROWSER.json.

Phase 8 release preparation adds a combined wheel/sdist with the built Reviewer, a clean-install loopback smoke test, publication-safe examples and media, and the open-source collaboration/release documents. Run the local release gate with:

python scripts/verify_release_candidate.py

It does not upload, tag, push, deploy, or otherwise publish anything. The publication-only checklist is in docs/RELEASE_CHECKLIST.md.

Validation benchmark

The public repository uses synthetic, GovernDiff-authored cases for its repeatable release and regression gates. They evaluate change types, clause pairing, semantic checks, Breaking classification, article remapping, confidence calibration, formats, and failure boundaries without redistributing third-party policy corpora.

python scripts/evaluate_phase3_benchmark.py --strict
PYTHONPATH=src python -m unittest discover -s tests -v

External-source evaluation material is maintained outside the public release snapshot until every source has an explicit redistribution decision. Public availability alone is not treated as a licence.

Accuracy contract

GovernDiff findings are evidence-backed review cues. A deterministic match such as scope-expanded says why the text triggered a rule; it does not claim to replace legal interpretation. Low-confidence semantic changes remain visible as substantive-text-changed instead of being silently discarded.

License

GovernDiff source code, synthetic examples, and public demo material are MIT licensed. Third-party dependency notices are recorded in reviewer-ui/THIRD_PARTY_NOTICES.md.